The long-term effects (10 years or more) of prostate cancer and treatment on clinical and patient-reported outcomes are not well understood. Furthermore, as patients live longer after their diagnosis, they are developing co-morbid conditions, experiencing cancer recurrences or progression and receiving secondary cancer therapies, all of which can affect their health and quality of life. A better understanding of these clinical events and their effects is essential to designing interventions to improve quality of life and for informing newly-diagnosed patients. We propose to use an existing and unique resource to improve our understanding of prostate cancer survivorship: the Prostate Cancer Outcomes Study (PCOS). The PCOS is a population-based cohort of men with prostate cancer followed longitudinally since their diagnosis in 1994-5. The dataset includes clinical and sociodemographic data, information on treatment and health-related quality of life (HRQOL) outcomes. The proposed study has the following three aims: 1) To characterize long-term (10-15 year) clinical outcomes, including biochemical recurrence (prostate-specific antigen), clinical disease progression, use of secondary cancer therapies and the onset or worsening of co-morbid illnesses and/or skeletal related events in a population-based cohort of prostate cancer survivors. 2) To assess the associations between these clinical outcomes and long-term disease-specific and general HRQOL. 3) To assess the independent associations of race/ethnicity and socioeconomic status (SES) with long- term clinical and HRQOL outcomes. To achieve these aims, we will collect 14-year data on disease recurrence/progression, receipt of secondary therapy, co-morbidity (including skeletal related and cardiovascular events), medication use, functional status and HRQOL in the surviving members of the PCOS cohort. The current PCOS cohort includes 2,348 men with prostate cancer from 6 SEER registries who have been followed since diagnosis with patient- reported data collected at 6,12, 24 and 60 months. Descriptive statistics will be used to achieve the first aim. For the second and third aims, appropriate multivariable statistical methodology will be used. When completed, this study will be the longest population-based prospective follow-up of prostate cancer survivors yet reported in the literature and will provide important information for prostate cancer survivors, clinicians, researchers and healthcare policy makers. Specifically, it will help newly-diagnosed patients make more informed decisions regarding treatment and will help researchers design novel interventions to improve the quality of life of prostate cancer survivors.